The invention generally relates to door hardware systems of the type typically used to operate a pair of bi-parting doors of a passenger transit vehicle. More particularly, the invention pertains to a central lock mechanism enabling locking of two door panels in either pushback or non-pushback.
The following background information is provided to assist the reader to understand the environment in which the invention will typically be used. The terms used herein are not intended to be limited to any particular narrow interpretation unless specifically stated otherwise in this document.
It is generally well known in the passenger transit vehicle art to employ a powered door operator having a locking mechanism for locking a door panel attached to the powered door operator and driven thereby to cover and uncover an aperture in the passenger transit vehicle. Among the many door operators to which the invention disclosed herein relates is the door hardware system disclosed in the text and figures of U.S. Pat. No. 6,032,416. FIG. 1 shows an opening in a sidewall of a railcar. Fixed to, or incorporated as part of the body of, the railcar above the aperture is a base plate disposed just above and horizontally along the length of opening. It is to this base plate that the door hardware system attaches to such railcar.
Regarding the locking feature of the door hardware system of the prior art, each outer door hanger has a contact bracket (not shown) attached to the top of its upper section. Atop the outer door hanger, a contact bracket (not shown) is designed to cooperate with a first door lock assembly to provide a lock for a door panel. Similarly, a second door lock assembly cooperates with a contact bracket (not shown), atop another outer door hanger to provided a lock for a second door panel. The first and second door lock assemblies are also mirror-symmetrical devices.
For this reason, the parts of the second door lock assembly are not described in detail for the sake of brevity. Reference can also be had to the figures of U.S. Pat. No. 6,032,416. As shown in FIGS. 4A-C, the first door lock assembly includes a lock member, a pivot pin, an unlock actuator, a pushback member, a latch lever, an emergency release rotor, a full lock switch and a pushback lock switch.
As shown in FIGS. 5A-C, the second door lock assembly includes a lock member and an unlock actuator. The pushback member, latch lever, emergency release rotor, full lock switch and pushback lock switch of assembly are shown, but not numerically denoted for brevity. Being door status switches, the full and pushback lock switches can be deployed with their first contacts providing input to a door controller (not shown).
Referring again to FIGS. 4A-C illustrating the first door lock assembly, the latch lever is pivotally connected at its upper end to the body of the assembly at a point above the right end of lock member. Latch lever has a cam (shown in dotted lines) on the other end of its pivot pin. Located at the lower end of this lever is the latch itself. The full lock switch is positioned behind the pushback lock switch, with both being secured to the body of the lock assembly. Pushback member is pivotally connected to the body, just to the right of pushback lock switch. The unlock actuator has its right end secured to the body of the assembly. The actuator has a push rod extending from its left end. The leftmost end of push rod connects by a pin to the upper left end of lock member and within the channel joint of the pushback member.
Pivotable about a pin, the lock member features lock step, a pushback step, a cam receptor slot and a lock arm formed as a part of its leftmost end. The cam receptor slot is formed in the top side of lock member near its right end and pushback step is formed on the bottom side of the lock member near its middle. Such lock step is formed in the lower right end of the lock member.
The lock members are disposed within first and second door lock assemblies, respectively, so as to be normally biased in the downward state. For the first door lock assembly, this is best shown in FIG. 4C. For the second door lock assembly, it is best shown in FIG. 5C. Specifically, starting with FIG. 2 with further reference to FIG. 4A, as the first door is being moved rightward towards the CLOSE POSITION by the motor and drive mechanism, the contact bracket, atop the outer door hanger, eventually slides left to right underneath the bottom side of the lock member.
As outer door hanger and door therewith continue rightward, the protuberance of the contact bracket encounters the left side of the lower end of the latch causing such latch to rotate counterclockwise. This counterclockwise rotation causes the cam of such latch to rotate out of engagement with the cam receptor slot of the lock member. With its right end being disengaged from the cam, the lock member then pivots clockwise about a pin so that its right end falls on top of the bracket. As the outer door hanger and door therewith close to within approximately 40 mm. of the CLOSE POSITION, the leftmost corner of the bracket is first caught by a pushback step due to the downward bias of the lock member, as shown in FIG. 4B. This causes the pushback member to pivot clockwise and engage the button of the pushback lock switch. With its two contacts closed, the switch closes its portion of the DCLC trainline and provides a pushback-locked signal to a DCU to indicate that the pushback lock has engaged (i.e., member has assumed the pushback-locked state). As the motor and drive mechanism continue to close the doors, the leftmost corner of the contact bracket moves through the pushback region between steps and is eventually caught by a lock step, as shown in FIG. 4C. This causes the lock member to pivot clockwise further about the pin so that its leftwardly extending arm engages the button of the full lock switch. With its contact closed, the switch sends to a DCU a fully-locked signal indicating that the full lock has now engaged. It is in this manner that the lock member assumes the fully-locked state wherein the leftmost corner of the contact bracket abuts against the lock step thereby preventing the outer door hanger and the first door therewith from being re-opened.
Due to the linkage of the drive mechanism, the second door is moved leftward simultaneously with the rightward movement of the first door. Specifically, starting again with FIG. 2 with reference to FIG. 5A, as the second door is being moved leftward towards the CLOSE POSITION, a contact bracket atop an outer door hanger eventually slides right to left underneath the bottom side of a lock member. As the outer door hanger and the second door therewith continue leftward, the protuberance of the bracket encounters the right side of the lower end of the latch in assembly causing that latch to rotate clockwise. This clockwise rotation causes the cam of that latch to rotate out of engagement with the cam receptor slot of a lock member. With its left end being disengaged from the latch cam, the lock member then pivots counterclockwise about its pin so that its left end falls on top of the bracket.
As outer door hanger and the door therewith close to within approximately 40 mm. of the CLOSE POSITION, the rightmost corner of the contact bracket is first caught by the pushback step of the lock member due to the downward bias operating on it, as shown in FIG. 5B. This causes the pushback member of the assembly to pivot counterclockwise and engage the button of its corresponding pushback lock switch. With its two contacts closed, this switch closes its portion of the DCLC trainline and provides a pushback-locked signal to a DCU to indicate that the pushback lock of the lock member has engaged (i.e., member has assumed the pushback-locked state).
As the motor and drive mechanism continue to close the doors, the rightmost corner of the contact bracket moves through the pushback region between the steps of the lock member and is eventually caught by the lock step, as shown in FIG. 5C. This causes the lock member to pivot counterclockwise further about its pin so that its rightwardly extending arm engages the button of the full lock switch for assembly. With its contact closed, this switch sends to a DCU a fully-locked signal indicating that the full lock of such lock member has now engaged. It is in this manner that the lock member assumes the fully-locked state wherein its lock step serves as an abutment against the rightmost corner of the contact bracket thereby preventing the second door panel from being re-opened. Moreover, due to the linkage of the mechanism, whenever any one of the lock members is fully locked, both doors are prevented from opening.
The aforementioned door operator has separate door lock assemblies, as is typical of prior art door hardware systems. As FIG. 2 shows, the door lock assemblies are distinct components, each attached to the base plate at a distinct spot above, and on opposite sides of, the doorway. Recent experience has revealed, however, that the use of separate door lock assemblies has its disadvantages.
As alluded to above, the door panels are essentially coupled together mechanically through drive the mechanism and related componentry. The door lock assemblies must therefore operate essentially in unison as the door panels are moved to the OPEN and FULL LOCK POSITIONS. This requires each door lock assembly to be precisely positioned on the base plate so that it will assume the same state at the same time as its partner. For example, as the door panels are closing, the door lock assemblies should each assume the pushback-locked state and then the fully-locked state nearly simultaneously. If one or both are out of position, one door lock assembly may conceivably remain unlocked when the other has properly assumed the fully-locked state.
Additionally, the lock assemblies incorporate complex components requiring adjustments to transmit linear motion of the actuator into rotary motion of the lock member in order to lock and unlock the doors.
As heretofore designed, the door lock assemblies thus require relatively frequent adjustment to make sure that they operate in unison. It would therefore be desirable to develop a lock mechanism whose design addresses the shortcomings in the existing technology, one that requires only minimal adjustment and incorporates fewer components.
The present invention teaches a lock mechanism enabling locking of a bi-parting set of right hand and left hand door panels respectively suspended from a right hand and left hand door operators, to be driven by such door operators for covering and uncovering an aperture disposed within a passenger transit vehicle, the lock mechanism is disposed intermediate such door operators. The lock mechanism is capable of operating in a pushback and non pushback arrangement providing a fully-locked state, for each of the two bi-parting doors of a passenger transit vehicle. The integrated design allows the central lock mechanism to be installed and/or maintained over a doorway with only minimal adjustments needed to assure that the door lock assemblies operate in unison. As compared to separate door lock assemblies for each door panel as is typical of prior art designs, the central lock mechanism enables the door panels to be closed and locked more reliably and with better sealing against weather and noise. Such lock mechanisms comprise a first and second block support assemblies having means for mounting to a passenger vehicle structure, a first and second lock member is rotatably disposed within the first and second block support assemblies, respectively. A mounting bracket is attached to the first and second block support assemblies and a plurality of rotary actuators are mounted to such mounting bracket. The rotary actuators engage the first and second lock members for moving such first and second lock members from a locking position into an unlocking position. A plurality of sensors are disposed within the lock mechanism for providing predetermined status signals when such first and second lock members are in such locking and pushback positions. A lever and cam arrangement are rotatably disposed within the first and second support block assemblies for manual unlocking of the door from the remote location via a flexible cable. A cover is provided to substantially shield such rotary actuator and sensors from access upon at least partial uncovering of such aperture.
It is, therefore, an one of the primary objects of the present invention to provide a central lock mechanism that is able to lock two doors within a single assembly, in lieu of the separate door lock assemblies typical of prior art designs.
Another object of the present invention is to provide a central door lock mechanism that requires only minimal adjustments to keep its door lock assemblies operating in unison.
Yet another object of the present invention is to provide a central door lock mechanism that has fewer components and is more tamperproof than its prior art predecessors.
A further object of the present invention is to provide a central lock mechanism whose door lock assemblies are capable of operating as a two-stage lock, i.e., providing pushback-locked and fully-locked states.
Yet a further object of the present invention is to provide a central lock mechanism whose door lock assemblies, when fully locked, enable the door panels when closed to provide better sealing against weather and noise than prior art door lock assemblies.
Still a further object of the present invention is to provide a central lock mechanism that provides a more reliable operation.
In addition to the objects and advantages listed above, various other objects and advantages of the invention will become more readily apparent to persons skilled in the relevant art from a reading of the detailed description section of this document. The other objects and advantages will become particularly apparent when the detailed description is considered along with the drawings and claims presented herein.